Adjustable plow



Feb. 13, 1940; 1. F. DAVIDSON ADJUSTABLE PLOW Filed July 30, 1938 4 Sh eets-Sheet 1 N WE INVENTOR Isaac E Davidson BY W ATTOR Y5 Feb. 13, 1940. F. DAVIDSON ADJUSTABLE PLOW Filed July 30, 1938 4 Sheets-Sheet 2 Feb. 13, 1940. I. F. DAVIDSON 2,190,056

' ADJUSTABLE PLOW Filed July 30, 1958 4 Sheets-Sheet 3 INVENTOR Isaac 1? Davidson I Patented Feb. 13, 1940 UNITED STATES. PATENT- OFFICE Isaac F. Davidson, Portland, Oreg.

' Application July 30, 1938, Serial No. 222,238

8 Claims.

My invention relates to adjustable plows of the type adapted to be carried at the front of trucks, tractors or similar vehicles for removing, leveling or making a pathway thru snow, or, in

general, for leveling or grading earth or similar material.

More particularly, my invention is concerned with an adjustable plow forming an attachment to a tractor of the caterpillar type, especially in tractors which are specifically adapted for use in snow, such as those described in my co-pending applications, Ser. No. 136,426 and 170,846.

An object of my invention is to provide a simple practical plow comprising adjustable ele l5- ments which may be easily controlled from the cab or drivers seat of the truck or tractor.

Another object of my invention is to providea snow plow particularly adaptable for sloping ground or hillsides, whereby a comparatively lev- 20 e1 roadway may be formed on the sloping ground for the tractor or truck to which the plow is attached. This specific object I accomplish by arranging the plow-shares of my device so that, when desired, only one side share or blade of 25 the plow need be used, and thus when used on a hillside for plowing the snow or grading the ground or other material, the plow-share on the high side may be used alone, thus removing the snow or other material on the high side and 80 transferring the same to the low side for the purpose of making a level roadway. Consequently, one of the important features of my plow is the fact that either share may be readily elevated and adjusted independently of the other.

35 A further object of my invention is to provide a plow having separate shares or blades so arranged that they may be converted from a clearing or diverting position to an accumulating and transferring position; thus, in addition to having 40 the shares or blades separately adjustable, having these so attached to the plow that they may be set at either an obtuse angle or acute angle with the direction of travel of the vehicle, and consequentlyforming either the usual V-shaped 5 plow or a scraper or leveler of inverted V-shape.

A still further object of my invention is to provide a plow, attached to'a tractor'or similar vehicle, of which all parts may quickly be raised as a unit in order to lift the entire plow over 50 obstacles, or to raise the plow out of the way when further use of the plow is not desired.

Another object of my invention is to provide a plow of the type indicated which, in addition to the usual plow-shares, will have auxiliary 55 blades to serve as a supplementary means of leveling the roadbed ahead of the tractor or truck, to provide such auxiliary blades so that they will function independently of the position of the main plow-shares, and to have these auxiliary blades in themselves separately and inde- 5 pendently adjustable.

All these and additional related objects I attain by constructing my plow and associated mechanism in the form hereinafter described with reference to the accompanying drawings.

In the drawings:

Fig. l is an assembly view of my invention combined with a certain type of snow tractor which I have found particularly adaptable and practical for use with my plow for snow;

Fig. 2 is a partial plan view corresponding to Fig, l but drawn to a larger scale;

Fig. 3 is a partial side elevation showing the main portion of my device in a certain operative position;

Fig. 4 is a corresponding fragmentary side elevation showing one of the plow-shares of Fig. 3

raised to inoperative position;

Fig. 5 is a partial side elevation similar to Fig. 3 but showing the entire plow raised to inoperative position;

Fig. 6 is a plan view conforming to Fig. 3;

Fig. '7 is a sectional elevation on the line l-l of Fig. 6 but drawn to a larger scale;

Fig. 8 is a sectional elevation on the line 88 of Fig. 6 illustrating certain parts of the operating mechanism but drawn to a considerably larger scale;

Fig. 9 is a front elevation of my plow with portions of the plow-shares broken away to show the auxiliary blades behind them;

Fig. 10 is a corresponding side elevation of the forward end of the plow, with the main plowshares in raised position to show the auxiliary blades;

Fig. 11 is a sectional plan on the line H--ll of Fig. 1 illustrating the actuating mechanism of my plow, but drawn to a larger scale than Fig. 1;

Fig. 12 is a corresponding side elevation of the mechanism shown in Fig; 11.

Fig. 13 is an enlarged detail of certain parts of the mechanism illustrated in Figs. 11 and 12;

Fig. 14 is a sectional plan on the line "-44 of Fig. l. drawn to a larger scale, illustrating also a type of hitch which may be used in connection with the tractor shown in Fig. 1, certain nonrelated parts, such as'side sheathing, being omitted from the tractor for clarity; and

Fig. 15 is a side elevation of the hitch illustrated in Fig. 14. u

My invention is shown in the drawings and described herein as used in connection with a tractor similar to that described in my co-pending application, Serial No. 136,426. However, the use of my plow is not confined to any particular type of tractor and may readily be used with other kinds of automotive vehicles, as previously mentioned.

The plow elements of my device are carried on a U-shaped frame I which comprises side beams 2 and 3 and a forward connecting member 4. The side beams 2 and 3 may be of any structural form tofurnish the required strength, and these side beams have their rear ends pivotally mounted as at 5 and 6 on the vehicle chassis (see Fig. 2).

The forward ends of the beams 2 and 3 slope downwardly and rearwardly as illustrated and the connecting member 4 which is rigidly secured to them is carried in a corresponding oblique position. Brackets I are attached by bolts near the upper edge of member 4. Removable shafts 8, joumaled in the brackets I, serve as pivotal mountings for the vertical plates 9 and ID, to which in turn are secured a pair of vertically curved plow-shares or blades H and I2 as shown in Figs. 2 and 6. The vertical plates 9 are considerably narrower than the plates Ill, so that the plowshares l l and I2 will be held at an angle to the center line of the tractor, for example, as shown in Fig. 2. The plowshares l I and I2 are similar but oppositely sloped, interchangeable, and extend from the center line to a short distance in excess of the over-all width of the'tractor or vehicle. When these plowshares are in lowered or active position, the rear edges of the supporting plates 9 and Ill will be contiguous with the front face of member 4, and the thrust of snow or other material which comes in contact with the plowshares II and I2 is transmitted to the side beams 2 and 3 and thus to the vehicle chassis.

Each of the plow-shares II and i2 may be raised or lowered independently of the other by means of twin elevating mechanisms (see Fig. 11) each of which comprises a crank l3, preferably located in the cab of the vehicle, adapted to rotate a drum M on which is wound a flexible cable l5 extending thru a suitable guide tube It to swivel connection with a clamp l'l located on the upper edge of the plow-shares II or 12. Preferably these clamps I! are located near the outer end of the plow-shares l l and [2 as shown. Thus rotation in the proper direction of either of the drums it causes the supporting plates 9 and ll! of the corresponding plow-share to pivot upwardly on its shaft 8 and thus swing such plow-share up out of operating position. The plow-share I2 is shown in such raised position in Figs. 4 and 10. In order to provide for rapid lowering of the plow-shares II and I2 from such raised position, each of the cranks l3 may be constructed as shown in detail in Fig. 13, namely, the hub E8, of each crank I3, is slidably and rotatably mounted on shaft l9. Shaft l9, thru suitable gearing, is adapted to rotate the corresponding drum M. The hub I8 is provided with diametrically opposite slots 20 so that when-the hub I8 is pressed inwardly the slots will engage a pin 2| rigidly disposed in the shaft l9, thus enabling rotation of the crank l3 to cause similar rotation of the shaft I9, when the particular plow-share is to be raised.

The raised plow-share may be held at any desired position by simply pushing the stem of the handle 22, which is slideably disposed in the end of the crank l3, into a hole in a bracket 23 secured to the vehicle framework. When it is desired to lower the raised plow-share the crank 13 is pulled outwardly causing the slots 20 to be disengaged from the pin 2| and simultaneously the stem of the handle 22 to become disengaged from the hole in the bracket 23. This allows the plow-share to drop by gravity causing the shaft l9 to spin within the hub l8. sired to lower the plow-share less rapidly, the rotation of the shaft I9 may be retarded by pulling on the crank l3 until the outer end of the hub l8 bears against a shoulder provided on the end of the shaft l9, whereby the frictional contact of the hub l8 and shoulder 24 serves as a brake.

The twin mechanisms just described for independently controlling the plow-shares and the independent pivotal mounting of the plow-shares, render my device especially suitable for plowing, leveling or grading over rough surfaces where the contour of the ground and the obstructions may necessitate frequent raising and subsequent lowering of either one share or the other.

Figs. 1, 2 and 5 show the plow-shares II and I2 as mounted on member 4 in the usual V-shaped plow position. This arrangement of the plowshares is suitable in general when my device is to be used to clear snow or other material from the path of the vehicle. In such case the plowshares H and I2 divide the mass and thrust it to each side of the path. However, when it is desired to use my device as a bull-dozer for grading, leveling or transfer purposes, the plowshares H and I2 may be interchanged to the position shown in Figs. 3, 6 and 9, that is, arranged in an inverted V-form. This is done very easily by removing the shafts B, disconnecting the clamp l1, and interchanging the plow-shares. With this arrangement the snow or other material will accumulate in front of the plow-shares H and I2 and thus be pushed along by the plow and vehicle to the place where it is desired to deposit the same for filling or leveling. In side hill work, particularly, the snow or other'material may be transferred from one side of the roadway to the other, and it is frequently desirable with such work for one of the plow-shares to be raised to an inoperative position, as previously stated, thereby facilitating the clearing or transferring of the snow or other material with the plowshare on one side only, usually on the high side, whereby the snow or other material is moved from the high side of the path to the low.

In addition to the provision for' independently and separately raising and lowering the plowshares II and I2, I provide for raising or lowering the entire forward plow assembly as a unit thru the operation or rotation of a single crank such as 25 (Figs. 11 and 12), which is preferably located in the cab of the vehicle near the cranks 13. The crank 25 is keyed to the shaft 26 carrying a worm 21, which worm meshes with a wormgear 28 mounted on a shaft 29 journaled transversely of the vehicle chassis in suitable bearings and having arms 30 secured at its outer ends. The arms 30 are coupled by forked rods 3| to bell-cranks 32. These bell-cranks 32 are keyed to the end of a transverse shaft 33 which is mounted at the forward end of the vehicle chassis in suitable bearings such as 3 (Figs. 6

and 8). The other arms of each bell-crank 32 carries a stub-shaft 35 which extends thru a slot 36 in the side beam 2 or 3. The stub-shafts 35 Should it be demay be attached to the bell-crank 32 as shown in u Fig. 8, and fitted with a roller 31 adapted to travel in ways 38 secured to the side beam adjacent the slot 36. Rotation of the crank 25 imparts rotary motion (at a much slower rate) to the worm gear 28 and shaft 29 with consequent arcuate movement of the arms 30 and bell-cranks 32, causing the rollers 31 to travel in the ways 38,and thus raise or lower the entire forward end of the frame I, the frame -I pivoting on the vehicle chassis at the points 5 and 6.

I have found it desirable, under many conditions,to provide auxiliary leveling blades 39 and 40 mounted in a vertical position on suitable brackets 51, which brackets are bolted to the member 4 of the supporting frame (see Figs. 9 and 10). The mounting of the blades 39 and 40 to the brackets 51 is preferably thru slotted connections 4! so as to permit a certain amount of vertical adjustment. These auxiliary blades 39 and 40 do not extend down as far as the plowshares H and i2, when the latter are in lowered position, but extend down sufflciently to serve as additional leveling means when either or both of the plow-shares II or l2 are raised, and these auxiliary blades also prevent mass material from clogging the track belts of the tractor. The inner pair of supporting brackets 51 for these auxiliary blades are larger than the outer pair, and thus the two auxiliary blades 39 and 40 are held in V-shape or plow formation.

The tractor on which I have shown my plow mounted in Figs. 1 and 2 is similarto the trac- I tor described in my co-pending application, Ser. No. 136,426. As an auxiliary means of steering the tractor, I have found it practical, under certain conditions, to provide a sled 43, attached to the tractor by means of a hitch 42. The particular hitch which I show comprises a pair of spaced plates 44 and45 pivotally mounted on the draw bar 46 at the rear of the tractor. (See Figs. 1, 2, 14 and 15.) A plate 4! is interposed between the spaced plates 44 and 45, and the interposed plate 41 carries an integral sheave 48, adapted to receive the flexible cables 49 and 50. The plate 41 and sheave 48 are rotatably connected to the plates 44 and 45 by a pivot pin a quadrant of the'sheave 48 when the tractorand sled are in alinement. The rear end of these cables are anchored to plate 41 and sheave 48 by a suitable fixture 53. The cables 49 and 50 extend forwardly and their forward ends are attached to rack bars54 slideably disposed at each side of the tractor. The rack bars 54 are caused to move longitudinally by means of cooperating pinons 55, which pinons are given rotary'motion thru the media of suitable gearing and clutches by which power is secured from the tractor transtogether instead of a tractor and a sled. Should it be desired to hitch two tractors together in tandem fashion in this manner, when both tractors are equipped with my plow device, this may easily be accomplished by removing, from the rear tractor, the plow-shares II and [2, the auxiliary blades 39 and 40, and the brackets 51 on member 4. Then the two outer brackets! are moved from the top edge to the bottom edge of member 4, as indicated by the broken lines in Fig. '7, a draw-bar similar to bar 52 is mounted between these lowered brackets I and the plate 4'! of the hitch is pivotally mounted on the drawbar.

Various modifications, of course, may be made in the specific shape and size of the plow-shares,

and the auxiliary blades of my device, and also in the shape and form of the brackets and other supporting members on which the plow-shares and blades are mounted, without departing from the principles of my invention. Similarly, other mechanical means for raising the plow or the separate plow-shares might be substituted for the particular mechanical means which I have suggested, and which I show as operated from the tractor cab. It is not my intention to limit my invention to any of the specific control means herein described.

Iclaim:

1. In a device of the character descrbed, a vehicle, a U-shaped frame pivoted on said vehicle, said frame comprising side portions and a cross member joining said side portions at the forward end, means on said vehicle for raising said frame, a pair of plow shares, each of said shares secured to a pair of brackets, one of said brackets extending forwardly further than the other, said brackets hinged to said cross member for up and down movement, the hinges of said brackets being in horizontal alinemen't, said hinges so arranged that said share assemblies may be removed or interchanged, means on said vehicle removably connected to each of said shares whereby either of said shares may be swung upwardly independently of the other.

2. In a device of the character described, a

vehicle, a bulldozer frame pivotally mounted on said vehicle and normally held in substantially portions and a cross member joining said side portions at the forward end, the plane of said cross member sloping downwardly and rearwardly, means on said vehicle for raising said frame, a pair of plow shares removably interchangeably hinged to said cross member, the hinges of said shares being in horizontal alinement, means on said vehicle removably connected to each of said shares whereby either of said shares may be swung upwardly independently of the'other, a pair of vertical auxiliary blades removably and adjustably secured to said cross member between said shares and said cross member.

3. In a device of the character described, a

track-laying tractor, a U-shaped frame pivoted on said track-laying tractor, said frame comprising side portions and a cross member joining said side portions at the forward end, means on said track-laying tractor for raising said frame, a pair of plow shares, each of said shares secured to a pair of vertical brackets, one of said brackets extending forwardly further than the other, said brackets hinged to said cross member for up and down movement, said hinges so arranged that said share assemblies may be removed or interchanged, means on said track-laying tractor connected to each of said shares whereby either ofsaid shares may be swung upwardly independently of the other, a pair of vertical auxiliary blades removably secured to said cross member between said shares and said cross member.'

4. In a device of the character described, a track-laying tractor, a bulldozer frame pivotally mounted on said track-laying tractor and normally held in substantially horizontal position, means on said track-laying tractor for raising said frame, a pair of plow shares, each of said shares secured to a pair of brackets, one of said brackets extending forwardly further than the other, said brackets hinged to the front end of said frame for up and down movement, said hinges so arranged that said share assemblies may be removed or interchanged, means on said track-laying tractor removably connected to each of said shares whereby either of said shares may be swung upwardly independently of the other, a pair of auxiliary blades, each of said auxiliary blades adjustably mounted on a pair of brackets secured to the front end of said frame, one of said last named brackets extending forwardly further than the other but said last named brackets being smaller than said first named brackets of said shares.

5. The combination described by claim 4 with the hinges of said first named brackets being in horizontal alinement.

6. In a device of the character described, a vehicle, a bulldozer frame pivotally mounted on said vehicle, and normally held in substantially horizontal position, means on said vehicle for raising said frame, a pair of plow shares, each of said shares secured to a pair of vertical brackets, one of said brackets extending forwardly further than the other, said brackets hinged to the front end of said frame for up and down movement, the hinges of said brackets being in horizontal alinement, said hinges so arranged that said share assemblies may be removed or interchanged, means on said vehicle connected to each of said shares whereby either of said shares may be swung upwardly independently of the other, a pair of auxiliary blades, each of said auxiliary blades adjustably mounted on apair of vertical brackets secured to the front end of said frame, one of said.last named brackets extending forwardly further than the other but said last named brackets being smaller than said first named brackets of said shares.

7. In a device of the character described, a vehicle, a. U-shaped frame pivoted on said vehicle and normally held in substantially horizontal position, said frame including side portions and a front member, a pair of plow shares,

each of said plow shares attached to a pair of brackets, one of saidbrackets extending forwardly further than the other, said brackets carried by said front member, said shares hinged for up and down movement, and means on said vehicle for swinging each of said shares upwardly independently of the other.

8. In a device of the character described, a vehicle, a U-shaped frame pivoted on said vehicle, said frame including side portions and a front member, the plane of said front member sloping downwardly and rearwardly, a pair of plow shares, each of said shares secured to a pair of brackets, said brackets hinged to said front member for up and down movement, means on said vehicle for swinging each of said shares upwardly independently of the other.

. ISAAC F. DAVIDSON. 

